The Effects of Ranavirus on Predator-Prey Dynamics
Amphibians globally are facing many threats, one of which is infection by ranavirus. Little is understood about how multiple stressors, such as disease and predation, can interact. I will evaluate the effect of the problematic amphibian pathogen ranavirus on larval amphibian prey by both an invertebrate predator (not susceptible to virus) and a susceptible amphibian predator. I will examine the behavior of larval leopard frogs (Rana pipiens) in response to infection and will analyze the effects of this behavior on timing of predation by dystiscid beetles and tiger salamander (Ambystoma tigrinum) larvae. This summer I will expose tadpoles to ranavirus at 0 (control) or high virion levels. After 24 hours of exposure groups of 5 tadpoles will enter a predator arena with dysticid beetle, larval tiger salamander, or no predator. Predator avoidance behaviors will be analyzed along with time to death and whether death occurred from ranavirus or predation. The prey seeking behaviors will also be analyzed by each predator. Individuals will be tested for ranavirus infection via qPCR analysis. Infected tadpoles often experience lethargy therefore expected results are that infected tadpoles will be consumed by the active forager sooner on average than uninfected individuals. Predation rates by the sit and wait predator will be lower on average for infected individuals than uninfected individuals.
Galvin, Danielle, "The Effects of Ranavirus on Predator-Prey Dynamics" (2020). IdeaFest. 135.